1. Field of Invention
The present invention relates generally to an automated tunnel-type laser scanning package identification and measuring system arranged about a high-speed conveyor belt used in diverse package routing and transport applications, and also to a method of identifying and measuring packages having bar code symbols on surfaces facing any direction with a 3-D scanning volume.
2. Brief Description of the Prior Art
In many environments, there is a great need to automatically identify and measure objects (e.g. packages, parcels, products, luggage, etc.) as they are transported along a conveyor structure. While over-the-head laser scanning systems are effective in scanning upwardly-facing bar codes on conveyed objects, there are many applications where it is not practical or otherwise feasible to ensure that bar code labels are upwardly-facing during transported under the scanning station.
Various types of xe2x80x9ctunnelxe2x80x9d scanning systems have been proposed so that bar codes can be scanned independent of their orientation within the scanning volume of the system. One such prior art tunnel scanning system is disclosed in U.S. Pat. No. 5,019,714 to Knowles. In this prior art scanning system, a plurality of single scanline scanners are orientated about a conveyor structure in order to provide limited degree of omni-directional scanning within the xe2x80x9ctunnel-likexe2x80x9d scanning environment. Notably, however, prior art tunnel scanning systems, including the system disclosed in U.S. Pat. No. 5,019,714, are incapable of scanning bar code systems in a true omni-directional sense, i.e. independent of the direction that a bar code faces as it is transported along the conveyor structure. At best, prior art scanning systems provide omni-directional scanning in the plane of the conveyor belt or in portions of planes orthogonal thereto. However, true omnidirectional scanning along the principal planes of a large 3-D scanning volume has not been hitherto possible.
Also, while numerous systems have been proposed for automatically identifying and measuring the dimensions and weight of packages along a high-speed conveyor, prior art systems have been very difficult to manufacture, maintain, and operate in a reliable manner without the use of human supervision.
Thus, there is a great need in the art for an improved tunnel-type automated laser scanning package identification/measuring system and a method of identifying and measuring packages transported along a high-speed conveyor system, while avoiding the shortcomings and drawbacks of prior art scanning systems and methodologies.
Accordingly, a primary object of the present invention is to provide a novel omni-directional tunnel-type automated package identification and measuring system that is free of the shortcomings and drawbacks of prior art tunnel-type laser scanning systems and methodologies.
Another object of the present invention is to provide a fully automated package identification and measuring system, wherein an omni-directional holographic scanning tunnel is used to read bar codes on packages entering the tunnel, while a package dimensioning subsystem is used to capture information about the package prior to entry into the tunnel.
Another object of the present invention is to provide a fully automated package identification and measuring system, wherein mathematical models are created on a real-time basis for both the geometry of the package and the position of the laser scanning beam used to read the bar code symbol thereon. Another object of the present invention is to provide a fully automated package identification and measuring system, wherein the mathematical models are analyzed to determine if collected and queued package identification data is spatially and/or temporally correlated with package measurement data using vector-based ray-tracing methods, homogeneous transformations, and object-oriented decision logic so as to enable simultaneous tracking of multiple packages being transported through the scanning tunnel.
Another object of the present invention is to provide a fully automated package identification and measuring system, wherein bar code symbols that have been placed on any surface of any package, including USPS trays and tubs, and other customer mailed products, including the bottom surface of the product, are automatically scanned during movement through the system.
Another object of the present invention is to provide such a tunnel-type system which can be used for high speed mail and parcel sorting systems (e.g. Large Package Sorting Systems (LPSS), Singulate and Scan Induction Units (SSIU), as well as luggage checking and tracking systems used in airport terminals, bus-stations, train stations, and the like.
Another object of the present invention is to provide such a tunnel-type system, which can read different bar code symbologies (e.g., Interleaved two of five, Code 128 and Code three of nine), code lengths, and formats in accordance with AIM and ANSI Standards.
Another object of the present invention is to provide such a tunnel-type system, in which a user-interface is provided for programming the bar code symbologies, code lengths and code formats handled by each laser scanning unit within the system.
Another object of the present invention is to provide such a tunnel-type system, for reading bar code symbols on packages having various types of symbol formats, such as ZIP Code symbols (six digits), Package Identification Code (PIC) symbols (sixteen characters), and Tray bar code symbols (ten digits).
Another object of the present invention is to provide such a tunnel-type system, for omni-directional scanning of bar code symbols on packages, parcels and products transported along a high-speed conveyor system at velocities in the range of about 100 to 520 feet per minute or greater.
Another object of the present invention is to provide such a tunnel-type system, in which a plurality of holographic laser scanning subsystems are mounted from a scanner support framework, arranged about a high-speed conveyor belt, and arranged so that each scanning subsystem projects a highly-defined 3-D omni-directional scanning volume with a large depth-of-field, above the conveyor structure so as to collectively provide omni-directional scanning with each of the three principal scanning planes of the tunnel-type scanning system.
Another object of the present invention is to provide such a tunnel-type system, in which each holographic laser scanning subsystem projects a highly-defined 3-D omni-directional scanning volume that has a large depth-of-field and is substantially free of spatially and temporally coincident scanning planes, to ensure substantially zero crosstalk among the numerous laser scanning channels provided within each holographic laser scanning subsystem employed in the system.
Another object of the present invention is to provide such a tunnel-type system, in which a split-type conveyor is used with a gap disposed between its first and second conveyor platforms, for mounting of an omni-directional projection-type laser scanning subsystem below the conveyor platforms and extending substantially the entire width of the conveyor platform.
Another object of the present invention is to provide such a tunnel-type system, wherein a plurality of holographic laser scanners are arranged about the conveyor system as to produce a bi-directional scanning pattern along the principal axes of a three-dimensional laser scanning volume.
A further object of the present invention is to provide a tunnel-type system, in which each holographic laser scanner employed in the system projects a three-dimensional laser scanning volume having multiple focal planes and a highly confined geometry extending about a projection axis extending from the scanning window of the holographic scanner and above the conveyor belt of the system.
Another object of the present invention is to provide an improved tunnel-type system, wherein bar code symbols downwardly facing the conveyor belt can be automatically scanned as they are transported through the system in a high-speed manner.
Another object of the present invention is to provide an improved method of identifying and measuring packages within a tunnel-scanning environment through which objects of various types can be conveyed at high transport speeds.
Another object of the present invention is to provide an automated package identification and measuring system characterized by: lower labor costs; higher load efficiency; perfect destination accuracy; extremely fast ID throughput; more accurate shipping charges; fast, accurate tracking and sorting; and precision package weights, shapes, and measurements.
Another object of the present invention is to provide an automated package identification and measuring system which can read bar codes anywhere on a parcel moving down a fast conveyor line: top; sides; front; rear; and bottom.
Another object of the present invention is to provide an automated package identification and measuring system which enables fully automated package handling on real world-sized bar codes.
Another object of the present invention is to provide an automated package identification and measuring system which doe not require any human intervention during handling.
Another object of the present invention is to provide an automated package identification and measuring system which can sort the package after bar code data on the package has been read and captured by the system software.
Another object of the present invention is to provide an automated package identification and measuring system which can measure and weigh the package, eliminating the xe2x80x9cguesstimatingxe2x80x9d often required by human operators.
Another object of the present invention is to provide an automated package identification and measuring system which enables exact weighing and measuring of packages, and thus minimizes wasted cargo space and more carrying capacity on every shipment, thereby allowing shippers to bill customers with greater precision, with fees keyed to package volume, shape, weight, and destination.
Another object of the present invention is to provide a novel method of automated package identification and measuring.
A further object of the present invention is to provide a novel way of and means for digitizing digital scan data while correlating laser scanning information.
A further object of the present invention is to provide a novel way of and means for decoding digital scan count data while correlating laser scanning information for use in various types of object tracking operations.
These and other objects of the present invention will become apparent hereinafter and in the Claims to Invention.